Vena cava filters are designed to capture emboli and prevent them from migrating via the blood stream into the pulmonary arteries. A vena cava filter is typically placed via a catheter inserted through a puncture in a vein. For insertion, the filter is collapsed within the catheter and is released after the catheter has accessed the vena cava.
Known vena cava filters in collapsed form have required relatively large diameter catheters and correspondingly large puncture openings which has limited the access point generally to the largest veins, i.e. the femoral and jugular veins. The relatively large puncture wound has at times produced complications.